Display control device, display control method, and computer program

ABSTRACT

There is provided a display control device capable of ensuring the user&#39;s field of vision while keeping the user safe when the user is using a see-through head-mounted display, the display control device including: a situation acquisition unit configured to acquire information about a situation where a see-through display is being used, and a display control unit configured to perform display control on the see-through display using the information acquired by the situation acquisition unit so that a display of the information on the see-through display gradually becomes clearly visible.

CROSS REFERENCE TO PRIOR APPLICATION

This application is a continuation of U.S. patent application Ser. No.15/101,739 (filed on Jun. 3, 2016), which is a National Stage PatentApplication of PCT International Patent Application No.PCT/JP2015/053312 (filed on Feb. 5, 2015) under 35 U.S.C. § 371, whichclaims priority to Japanese Patent Application No. 2014-030945 (filed onFeb. 20, 2014), which are all hereby incorporated by reference in theirentirety.

TECHNICAL FIELD

The present disclosure relates to display control devices, displaycontrol methods, and computer programs.

BACKGROUND ART

A display device which is worn on the head and is used to view video,i.e., a head-mounted display (HMD), is well known (see, for example.Patent Literature 1, etc.). A head-mounted display has an optical unitfor each of the left and right eyes, and is also used in combinationwith headphones, and is thereby configured to be capable of controllingvisual sensation and auditory sensation. There have recently beenadvances in techniques for a so-called see-through head-mounted display,which allows the user wearing the display to see a real scene at whichthe user's line of sight is aimed.

CITATION LIST Patent Literature

Patent Literature 1: JP 2013-257457A

SUMMARY OF INVENTION Technical Problem

A see-through head-mounted display continues to be worn by the userduring the use of the head-mounted display, so that the display ispresent in front of the user's eyes. Therefore, notification informationwhich notifies the user of the arrival of a mail call, or the like maybe displayed on the display at a timing when the user is not expectingit. If notification information is suddenly displayed on the display,the user's field of vision is partially blocked by the notificationinformation, which is dangerous.

Also, if notification information is caused to flicker or move duringthe use of a see-through head-mounted display in order to attract theuser's attention, the user's attention is attracted by the flickering ormovement, which is dangerous. In addition, if any information continuesto be displayed in a portion of the field of vie, the user's field ofvision is partially blocked by the information, which is dangerous.

With the above in mind, the present disclosure provides a novel andimproved display control device, display control method, and computerprogram which are capable of ensuring the user's field of vision whilekeeping the user safe when the user is using a see-through head-mounteddisplay.

Solution to Problem

According to the present disclosure, there is provided a display controldevice including: a situation acquisition unit configured to acquireinformation about a situation where a see-through display; and a displaycontrol unit configured to perform display control on the see-throughdisplay using the information acquired by the situation acquisition unitso that a display of the information on the see-through displaygradually becomes clearly visible.

According to the present disclosure, there is provided a display controlmethod including: acquiring information about a situation where asee-through display is being used; and performing display control on thesee-through display using the acquired information so that a display ofthe information on the see-through display gradually becomes clearlyvisible.

According to the present disclosure, there is provided a computerprogram for causing a computer to execute: acquiring information about asituation where a see-through display is being used; and performingdisplay control on the see-through display using the acquiredinformation so that a display of the information on the see-throughdisplay gradually becomes clearly visible.

Advantageous Effects of Invention

As described above, according to the present disclosure, a novel andimproved display control device, display control method, and computerprogram which are capable of ensuring the user's field of vision whilekeeping the user safe when the user is using a see-through head-mounteddisplay, can be provided.

Note that the effects described above are not necessarily limited, andalong with or instead of the effects, any effect that is desired to beintroduced in the present specification or other effects that can beexpected from the present specification may be exhibited.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is an illustrative diagram showing an external appearance exampleof a head-mounted display 100 according to an embodiment of the presentdisclosure.

FIG. 2 is an illustrative diagram showing an external appearance exampleof a head-mounted display 100 according to an embodiment of the presentdisclosure.

FIG. 3 is an illustrative diagram showing a functional configurationexample of a head-mounted display 100 according to an embodiment of thepresent disclosure.

FIG. 4A is an illustrative diagram showing an example of an image whichis displayed on a display unit 110 of a head-mounted display 100according to an embodiment of the present disclosure.

FIG. 4B is an illustrative diagram showing an example of an image whichis displayed on a display unit 110 of a head-mounted display 100according to an embodiment of the present disclosure.

FIG. 4C is an illustrative diagram showing an example of an image whichis displayed on a display unit 110 of a head-mounted display 100according to an embodiment of the present disclosure.

FIG. 4D is an illustrative diagram showing an example of an image whichis displayed on a display unit 110 of a head-mounted display 100according to an embodiment of the present disclosure.

FIG. 5 is an illustrative diagram showing a graph indicating an exampleof changes in the transparency of an icon 131 displayed on a displayunit 110 (or the luminance of the display unit 110).

FIG. 6A is an illustrative diagram showing a graph indicating an exampleof changes in the transparency of an icon 131 displayed on a displayunit 110 (or the luminance of the display unit 110).

FIG. 6B is an illustrative diagram showing a graph indicating an exampleof changes in the transparency of an icon 131 displayed on a displayunit 110 (or the luminance of the display unit 110).

FIG. 7A is an illustrative diagram showing an example of an image whichis displayed on a display unit 110 of a head-mounted display 100according to an embodiment of the present disclosure.

FIG. 7B is an illustrative diagram showing an example of an image whichis displayed on a display unit 110 of a head-mounted display 100according to an embodiment of the present disclosure.

FIG. 7C is an illustrative diagram showing an example of an image whichis displayed on a display unit 110 of a head-mounted display 100according to an embodiment of the present disclosure.

FIG. 8 is an illustrative diagram showing a specific example of acalculation method which is used during execution of display control onan icon according to the user's line of sight.

FIG. 9A is an illustrative diagram showing an example of an image whichis displayed on a display unit 110 of a head-mounted display 100according to an embodiment of the present disclosure.

FIG. 9B is an illustrative diagram showing an example of an image whichis displayed on a display unit 110 of a head-mounted display 100according to an embodiment of the present disclosure.

FIG. 9C is an illustrative diagram showing an example of an image whichis displayed on a display unit 110 of a head-mounted display 100according to an embodiment of the present disclosure.

FIG. 10 is a flowchart showing an operation example of the head-mounteddisplay 100 according to an embodiment of the present disclosure.

DESCRIPTION OF EMBODIMENT(S)

Hereinafter, (a) preferred embodiment(s) of the present disclosure willbe described in detail with reference to the appended drawings. In thisspecification and the appended drawings, structural elements that havesubstantially the same function and structure are denoted with the samereference numerals, and repeated explanation of these structuralelements is omitted.

Note that description will be provided in the following order.

1. Embodiments of the Present Disclosure

1.1. External Appearance Examples of Head-Mounted Display

1.2. Functional Configuration Examples of Head-Mounted Display

1.3. Operation Examples of Head-Mounted Display

2. Conclusion

1. EMBODIMENTS OF THE PRESENT DISCLOSURE

[1.1. External Appearance Examples of Head-Mounted Display]

Firstly, an external appearance example of a head-mounted displayaccording to an embodiment of the present disclosure will be described.FIG. 1 is an illustrative diagram showing an external appearance exampleof a head-mounted display 100 according to an embodiment of the presentdisclosure.

As shown in FIG. 1, the head-mounted display 100 is an eyeglassesdisplay device provided with a display unit 110 including a right-eyedisplay unit 110R and a left-eye display unit 110L. The head-mounteddisplay 100 is a so-called see-through head-mounted display, whichallows the user to view a screen superimposed on a real-world field ofview.

The head-mounted display 100 is configured so that nose pads 101 serveas a sensor for determining whether the display is worn, by detectingthe touch of the user's (viewer's) nose tip on the nose pads.

The display unit 110 may include, for example, an organic EL display.The display unit 110 is controlled so that the display of the displayunit 110 is switched between a mode in which an image is not displayed(see-through mode), a mode in which an image is displayed andsuperimposed on the user's read-world field of view (image displaymode), and a mode in which an image is displayed on only one of the twodisplay units (single-eye display mode).

The head-mounted display 100 receives an image signal, by wire orwirelessly, from an external device (a personal computer, a smartphone,a tablet-type mobile terminal, etc.), and displays an image on thedisplay unit 110 on the basis of the received image signal.

In the foregoing, an external appearance example of the head-mounteddisplay 100 according to an embodiment of the present disclosure hasbeen described with reference to FIG. 1. Next, another externalappearance example of the head-mounted display will be described. FIG. 2is an illustrative diagram showing an external appearance example of ahead-mounted display 100′ according to an embodiment of the presentdisclosure.

As shown in FIG. 2, the head-mounted display 100′ is an eyeglassesdisplay device which includes a mounting unit having a frame structurewhich extends across half the circumference of the head from one of boththe sides of the head to the other through the back of the head. Thehead-mounted display 100′ is provided with a display unit 110′ includinga right-eye the display unit 110R′ and a left-eye the display unit110L′.

The head-mounted display 100 shown in FIG. 1 and the head-mounteddisplay 100′ shown in FIG. 2 can allow the user to view a screensuperimposed on the read-world field of view. However, as describedabove, the see-through head-mounted display continues to be worn by theuser during the use of the head-mounted display, so that the display ispresent in front of the user's eyes. Therefore, notification informationwhich notifies the user of the arrival of a mail, call, or the like maybe displayed on the display at a timing when the user is not expectingit. If notification information is suddenly displayed on the display,the user's field of vision is partially blocked by the notificationinformation, which is dangerous.

Also, if notification information is caused to flicker or move duringthe use of the see-through head-mounted display in order to attract theuser's attention, the user's attention is attracted by the flickering ormovement, which is dangerous. In addition, if any information continuesto be displayed in a portion of the field of view, the user's field ofvision is partially blocked by the information, which is dangerous.

With the above in mind, in an embodiment of the present disclosure, ahead-mounted display for ensuring the user's field of vision whilekeeping the user safe will be described.

[1.2. Functional Configuration Examples of Head-Mounted Display]

Next, a functional configuration example of a head-mounted displayaccording to an embodiment of the present disclosure will be described.FIG. 3 is an illustrative diagram showing a functional configurationexample of a head-mounted display 100 according to an embodiment of thepresent disclosure. The functional configuration example of thehead-mounted display 100 according to an embodiment of the presentdisclosure will now be described with reference to FIG. 3.

As shown in FIG. 3, the head-mounted display 100 according to anembodiment of the present disclosure includes a sensor unit 101, asystem controller 102, a display unit 110, a sensor signal processingunit 111, a sensor control unit 112, an image capture unit 113, acaptured image signal processing unit 114, an image capture control unit115, an audio input unit 116, an audio output unit 117, an audio signalprocessing unit 118, an audio generation unit 119, an image generationunit 120, a displayed image processing unit 121, a display control unit122, a display drive unit 123, a communication unit 124, and a storageunit 125.

The system controller 102, which includes, for example, a microcomputerincluding a central processing unit (CPU), a read only memory (ROM), arandom access memory (RAM), a non-volatile memory unit, and an interfaceunit, may function as a control unit which controls the entirety of thisembodiment. The system controller 102 controls each unit according to aninternal operating program so that a required image is displayed on thedisplay unit 110. The system controller 102 may also function as anexample of a situation acquisition unit of the present disclosure.Specifically, the system controller 102 acquires information about asituation where the head-mounted display 100 is being used, on the basisof details of signals sent from the sensor signal processing unit 111,the captured image signal processing unit 114, and the audio signalprocessing unit 118 (described below).

The sensor unit 101 is a sensor which is typically mounted in thevicinity of the display unit 110. The sensor unit 101, which includes,for example, an acceleration sensor, a gyroscopic sensor, a magneticsensor, an atmospheric pressure sensor, or the like, can detect, forexample, a motion of the head, a motion of the neck, a motion of thehead-mounted display 100, or the like, as a signal corresponding to amotion of the user. The sensor unit 101 sends the sensor signal to thesensor signal processing unit 111.

The sensor unit 101 also processes signals from sensor systems which areused by the user to operate the head-mounted display 100, such as acapacitive sensor, buttons, a global positioning system (GPS), and thelike. Note that the positions where the input devices such as thecapacitive sensor, buttons. GPS, and the like are provided are notlimited to a region in the vicinity of the display unit 110.

The image capture unit 113 is provided as a sensor for detecting theuser's visual sensation, for example, in the vicinity of the displayunit 110, to capture an image of the user's eyes. The head-mounteddisplay 100 can perform image analysis on the image of the user's eyescaptured by the image capture unit 113, to detect the user'sline-of-sight direction, focal length, pupil size, or eye funduspattern, whether the user's eyelid is open or closed, or the like. Notethat the detection of the user's line-of-sight direction, focal length,pupil size, or eye fundus pattern, whether the user's eyelid is open orclosed, or the like, may be performed by a light emission unit foremitting light to the user's eyes, which is provided in the vicinity ofthe display unit 110, and a light reception unit for receiving lightreflected by the eyes. For example, the thickness of the user'scrystalline lens can be detected on the basis of a light signal receivedby the light reception unit.

The sensor control unit 112 performs sensor control according to aninstruction from the system controller 102 to determine which sensor isdriven at what timing, or what drive method is used, or the like. Thesensor signal processing unit 111 performs various numerical processessuch as average, variance, and the like, as processes which areperformed before sending a sensor signal from the sensor unit 101 to thesystem controller 102.

In this embodiment, the user's operation may be required in order toturn on/off power supply, start or end displaying various informationimages, change details of an image, adjust display such as a luminancelevel, a color, or the like, change a display area on a display screen,or the like. For example, in order to allow these user's operations(detection of trigger for processing operations), an operation unitprovided as an operation key or operation dial which is operated by theuser, and an operation detection mechanism for detecting an operation onthe operation unit, are provided so that the system controller 102 candetect the user's operation, although not shown in FIG. 3.Alternatively, instead of providing such an operation unit, the systemcontroller 102 may determine the user's intention to operate or anappropriate operation process, on the basis of the user's situationdetected by the sensor unit 101 (e.g., a motion of the eye, a behavioror state of the body, etc.), and perform a process corresponding to theresult of the determination.

Moreover, the head-mounted display 100 may be configured to be capableof detecting external information (detection information, such as asituation around the display device, the place, the date and time,conditions of a subject, etc.) using the sensor unit 101. The systemcontroller 102 may determine an appropriate operation process on thebasis of the external information, and perform the process.

The audio generation unit 119 performs an audio synthesis process togenerate an audio signal such as a message voice or the like, orgenerates an audio signal such as an electronic sound or the like whichis to be presented to the user, according to an instruction from thesystem controller 102. The audio output unit 117 has, for example, aspeaker or earphone speaker (not shown) provided in the head-mounteddisplay 100, and an amplifier circuit for the speaker. The audio signalgenerated by the audio generation unit 119 is supplied to the audiooutput unit 117, so that the user can hear a message voice, anelectronic sound, or the like. Note that the audio output unit 117 maybe configured as a so-called bone-conduction speaker.

The audio input unit 116, which includes a microphone amplifier unit foramplifying an audio signal obtained by a microphone and an A/Dconverter, outputs audio data to the audio signal processing unit 118.The audio signal processing unit 118 includes, for example, a digitalsignal processor, a D/A converter, and the like. Audio data obtained bythe audio input unit 116 or audio data generated by the audio generationunit 119 is supplied to the audio signal processing unit 118.

The audio signal processing unit 118 performs processes such as soundvolume adjustment, sound quality adjustment, sound effect, and the likeon the supplied audio data under the control of the system controller102. Thereafter, the audio signal processing unit 118 converts theprocessed audio data into an analog signal, and supplies the analogsignal to the audio output unit 117. Note that the audio signalprocessing unit 118 is not limited to a configuration for performingdigital signal processing, and may perform signal processing using ananalog amplifier or an analog filter. The audio signal output from theaudio signal processing unit 118 is output as a sound from the earphonespeaker of the audio output unit 117. Such a configuration allows theuser to hear external sounds collected by the audio input unit 116 orsounds generated by the audio generation unit 119.

The image generation unit 120 generates an image signal under thecontrol of the system controller 102. The system controller 102 causesthe image generation unit 120 to generate an image signal from which animage to be presented to the user is generated, on the basis ofinformation or numerical values from the components, and therebygenerates an image signal as a picture image, a graph image, a characterdisplay image, an image for warning the user, or other images. The imagegeneration unit 120 supplies the generated image signal to the displayedimage processing unit 121.

The displayed image processing unit 121, which includes, for example, avideo processor, performs various display processes on the image signalsupplied from the image generation unit 120. The displayed imageprocessing unit 121 can perform luminance level adjustment, colorcorrection, contrast adjustment, sharpness (contour emphasis)adjustment, and the like on the image signal. The displayed imageprocessing unit 121 also adjusts settings for a display position on adisplay screen in the display unit 110. In addition, the displayed imageprocessing unit 121 may be configured to be capable of performingprocesses, including: image effect processes, such as generation of anenlarged image by enlarging a portion of an image signal, generation ofa reduced image by reducing a portion of an image signal, soft focus,mosaic, luminance reversal, highlight display (emphasized display) of aportion of an image, changing of the entire chromatic atmosphere, andthe like; separation and combination of an image signal for imagedivision display; the process of generating a character image or apicture image, and combining the generated image with an image signalsupplied from the image generation unit 120; and the like. The displayedimage processing unit 121 receives an image signal generated by theimage generation unit 120, performs a signal process required fordisplaying on the image signal, and supplies the resultant signal to thedisplay drive unit 123.

The display drive unit 123 includes a pixel drive circuit fordisplaying, on the display unit 110, the image signal supplied from thedisplayed image processing unit 121. Specifically, the display driveunit 123 applies a drive signal to pixels arranged in a matrix in thedisplay unit 110, at respective predetermined horizontal/vertical drivetimings, according to the image signal, and thereby causes the displayunit 110 to display. The display drive unit 123 can also control theluminances of the pixels of the display unit 110 so that the entirety ora portion of the screen is in the see-through mode.

The display control unit 122 controls a process operation of thedisplayed image processing unit 121, an operation of the display driveunit 123, and an image displayed on the display unit 110 (including aprocess for each of the right and left display units 110R and 110L)according to an instruction from the system controller 102, andinstructs the displayed image processing unit 121 to perform signalprocessing. The display control unit 122 also controls the display driveunit 123 so that the display drive unit 123 is switched between thesee-through mode, the image display mode, and the single-eye displaymode.

The image capture unit 113 includes: a lens system including an imagecapture lens, a diaphragm, a zoom lens, a focusing lens, and the like; adrive system for causing the lens system to perform a focusing operationor a zooming operation; a solid-state imaging element array fordetecting captured image light obtained by the lens system, andperforming photoelectric conversion to generate a captured image signal;and the like. Examples of the solid-state imaging element array includea charge coupled device (CCD) sensor array, and a complementary metaloxide semiconductor (CMOS) sensor array. In this embodiment, the imagecapture unit 113 captures an image of a scene in front of the userwearing the head-mounted display 100. Of course, the image capture unit113 may capture an image of a scene in other directions, such as a scenebehind the user or the like.

The captured image signal processing unit 114, which includes a samplehold/automatic gain control (AGC) circuit which performs gain adjustmentor wave shaping on a signal obtained by the solid-state imaging elementof the image capture unit 113, and a video A/D converter, obtains acaptured image signal in the form of digital data. The captured imagesignal processing unit 114 may also perform a white balance process, aluminance process, a color signal process, a shake correction process,or the like on a captured image signal.

The image capture control unit 115 controls operations of the imagecapture unit 113 and the captured image signal processing unit 114according to an instruction from the system controller 102. The imagecapture control unit 115 performs control to turn on/off operations ofthe image capture unit 113 and the captured image signal processing unit114, for example. The image capture control unit 115 may also performcontrol (motor control) to cause the image capture unit 113 to performoperations such as autofocusing, automatic exposure adjustment,diaphragm adjustment, zooming, changing of the focal point, and thelike. Note that when the image capture unit 113 is provided with amovable mechanism capable of changing the direction of the image capturelens toward a subject, the image capture control unit 115 may change thedirection of the image capture lens in the image capture unit 113 bycontrolling the operation of the movable mechanism according to aninstruction from the system controller 102.

The image capture control unit 115 may also include a timing generator.The image capture control unit 115 may control signal processingoperations of the solid-state imaging element, and the sample hold/AGCcircuit and video A/D converter of the captured image signal processingunit 114, according to a timing signal generated by the timinggenerator. In addition, the timing control may be used to performvariable control on the frame rate of image capture.

Moreover, the image capture control unit 115 may control the imagecapture sensitivity or signal processing of the solid-state imagingelement and the captured image signal processing unit 114. For example,in order to control the image capture sensitivity, the image capturecontrol unit 115 may control the gain of a signal read from thesolid-state imaging element, black level settings, various coefficientsfor captured image signal processing in the digital data phase, acorrection amount for a shake correction process, or the like. In orderto control the image capture sensitivity, the image capture control unit115 can perform a general sensitivity adjustment in which a wavelengthband is not particularly taken into account, a sensitivity adjustment inwhich the sensitivity of image capture in a particular wavelength band,such as an infrared region, an ultraviolet region, or the like, isadjusted (e.g., image capture where the particular wavelength band iscut off), or the like. The sensitivity adjustment according towavelength can be carried out by insertion of a wavelength filter in theimage capture lens system, or a wavelength filter calculation processperformed on a captured image signal. In these cases, the image capturecontrol unit 115 can perform sensitivity control by controlling theinsertion of a wavelength filter, specifying a filter calculationcoefficient, or the like.

A captured image signal obtained by the image capture unit 113 and thecaptured image signal processing unit 114 is supplied together with aninformation image signal generated by the image generation unit 120 tothe displayed image processing unit 121. The displayed image processingunit 121 performs the above signal processes on the captured imagesignal and the information image signal, and also performs a signalprocess for screen division (image synthesis process) on the capturedimage signal and the information image signal in order to simultaneouslydisplay a captured image and an information image on the display unit110.

An image signal obtained by the synthesis process in the displayed imageprocessing unit 121 is supplied to the display drive unit 123, anddisplayed on the display unit 110, so that a captured image and otherimages are simultaneously displayed on the display unit 110. In otherwords, the user can view various images while viewing an image capturedby the image capture unit 113.

The user may need to perform operations for starting and ending of animage capture operation, a zooming operation, a focusing operation, acaptured image adjustment, and the like. Of course, the user may alsoneed to perform operations for turning on/off of power supply, startingand ending of displaying of various information images, changing ofdetails of an image, display adjustment of a luminance level, a color,etc., changing of a display region on a display screen, and the like.For these operations (triggers for the operations), the head-mounteddisplay 100 may be provided with an operation unit such as an operationkey or the like. Alternatively, the system controller 102 may determinethe user's intention to operate or an appropriate operation process onthe basis of the user's conditions (e.g., a motion of the eye, abehavior or state of the body, etc.) detected by the sensor unit 101,and perform a process corresponding to the determination result.Moreover, the head-mounted display 100 may be configured to be capableof detecting external information (detection information, such as asituation around the display device, the place, the date and time,conditions of a subject, etc.), and the system controller 102 maydetermine an appropriate operation process on the basis of the externalinformation, and perform the process.

The storage unit 125, which is a part that records and retrieves datawith respect to a predetermined recording medium, is implemented as, forexample, a hard disk drive (HDD) or a solid-state drive (SSD). Ofcourse, the recording medium may be various media, such as a solid-statememory (a flash memory etc.), a memory card including a fixed memory, anoptical disc, a magneto-optic disc, a hologram memory, and the like. Thestorage unit 125 may be adapted, according to the employed recordingmedium, to be capable of recording and retrieving. For example, imagedata as a captured image signal which has been captured by the imagecapture unit 113 and processed by the captured image signal processingunit 114, image data received by the communication unit 124, and variousinformation image signals generated by the image generation unit 120 maybe supplied to the storage unit 125. In addition, audio data obtained bythe audio input unit 116, audio data received by the communication unit124, and audio data generated by the audio generation unit 119 may alsobe supplied to the storage unit 125.

The storage unit 125 performs an encoding process on the supplied imagedata or audio data in order to record the data to a predeterminedrecording medium, and records the data to the recording medium, underthe control of the system controller 102. The storage unit 125 alsoretrieves image data or audio data recorded in the recording medium, andoutputs the data, under the control of the system controller 102. Thedata retrieved by the storage unit 125 may be any data that is to bedisplayed, such as moving image contents (movies, video clips, etc.),still image contents which are captured by a digital still camera or thelike and recorded in a recording medium, data of electronic books andthe like, data used on a computer (image data, text data, spreadsheetdata and the like which are created by the user using a personalcomputer or the like), game images, and the like.

The communication unit 124 exchanges data with external devices.Examples of the external devices include an image capture device, suchas a video camera, a digital still camera, and the like, which has acommunication function, a computer device, a smartphone, a smartwatch, avideo storage device, AV devices, such as a television set and the like,a network server device, and the like. The communication unit 124 may beconfigured to perform network communication, for example, throughshort-distance radio communication with respect to a network accesspoint, according to a scheme such as wireless LAN, Bluetooth (registeredtrademark), or the like, or may be configured to perform direct radiocommunication with external devices having a corresponding communicationfunction. When the external device is an image capture device, datatransmitted from the external device to the head-mounted display 100 maybe image data captured by the image capture device. Alternatively, whenthe external device is a content source device, data transmitted fromthe external device to the head-mounted display 100 may be any data thatis to be displayed, such as moving image contents (movies, video clips,etc.), still image contents which are captured by a digital still cameraor the like and recorded in a recording medium, data of electronic booksand the like, data used on a computer (image data, text data,spreadsheet data and the like which are created by the user using apersonal computer or the like), game images, and the like.

Audio data obtained by the audio input unit 116, audio data retrieved bythe storage unit 125, and audio data received by the communication unit124 are supplied to the audio signal processing unit 118 according to aninstruction from the system controller 102. Therefore, the user can hearexternal sounds when an image is captured, view and hear an image andsounds retrieved by the storage unit 125, and view and hear an image andsounds received by the communication unit 124 while wearing the device.In particular, an image obtained by the image generation unit 120 issupplied together with the captured image, or retrieved image, orreceived image to the displayed image processing unit 121, so thatvarious information images are displayed together with the capturedimage, or retrieved image, or received image on the display unit 110.Audio data generated by the audio generation unit 119 is supplied, at atiming when the audio data is generated, to the audio signal processingunit 118, so that the user can hear a message voice, a warning sound, orthe like generated by the audio generation unit 119 while hearing, forexample, external sounds, retrieved sounds, or received sounds.

In addition to operations of the display system and operations involvedin the image capture function, the system controller 102 may determinewhether to trigger operation controls for retrieval, cuing up,fast-forwarding/fast-backwarding, pausing, recording, and the like inthe storage unit, and operation controls involved in transmission andreception by the communication unit. Also, in this case, an operationunit such as an operation key or the like which is operated by the usermay be provided, and a process corresponding to the operation may beperformed. Alternatively, the system controller 102 may determine theuser's intention to operate or an appropriate operation process on thebasis of the user's conditions (e.g., a motion of the eye, a behavior orstate of the body, etc.) detected by the sensor unit 101, and perform aprocess corresponding to the determination result. Moreover, thehead-mounted display 100 may be configured to be capable of detectingexternal information (detection information, such as a situation aroundthe display device, the place, the date and time, conditions of asubject, etc.), and the system controller 102 may determine anappropriate operation process on the basis of the external information,and perform the process.

When the head-mounted display 100 configured as shown in FIG. 3 isoperating in the image display mode or the single-eye display mode, thenif there is an incoming mail, call, or the like to a device external tothe head-mounted display 100 or the head-mounted display 100 itself, thesystem controller 102 performs a process of displaying, on the displayunit 110, an image (e.g., a predetermined icon) indicating the arrivalof a mail, call, or the like. In this case, the system controller 102displays the image indicating the arrival on the display unit 110 whilechanging the transparency of the icon (or the luminance of the displayunit 110) instead of suddenly displaying the image on the display unit110. By thus displaying an image indicating the arrival of a mail, call,or the like on the display unit 110 while changing the transparency ofthe icon (or the luminance of the display unit 110), the head-mounteddisplay 100 according to this embodiment can ensure the field of visionof the user wearing the head-mounted display 100 while keeping the usersafe.

Examples of an image displayed on the display unit 110 of thehead-mounted display 100 according to an embodiment of the presentdisclosure will be described. FIGS. 4A to 4D are illustrative diagramsshowing examples of an image displayed on the display unit 110 of thehead-mounted display 100 according to an embodiment of the presentdisclosure, where an icon is displayed when an interrupt, such as thearrival of a mail or the like, occurs. Note that FIGS. 4A to 4D show ascene which is viewed through the display unit 110 by the user of thehead-mounted display 100, in addition to an image which is displayed onthe display unit 110 by the head-mounted display 100.

FIG. 4A shows an example of an image which is displayed on the displayunit 110 immediately after the occurrence of an interrupt, such as thearrival of a mail or the like. The system controller 102 displays anicon indicating the occurrence of an interrupt on the display unit 110.In this case, the system controller 102 instructs the display controlunit 122 to increase the transparency of an icon 131 displayed on thedisplay unit 110 or decrease the luminance of the display unit 110immediately after the occurrence of an interrupt, such as the arrival ofa mail or the like. In other words, the system controller 102 performscontrol so that the displayed icon 131 is less easily recognizedimmediately after the occurrence of an interrupt, such as the arrival ofa mail or the like.

FIG. 4B shows an example of an image which is displayed on the displayunit 110 a predetermined period of time (e.g., 100 to 200 msec) afterthe state shown in FIG. 4A. FIG. 4C shows an example of an image whichis displayed on the display unit 110 a predetermined period of time(e.g., 100 to 200 msec) after the state shown in FIG. 4B. As shown inFIGS. 4B and 4C, the system controller 102 instructs the display controlunit 122 to gradually decrease the transparency of the icon 131 orincrease the luminance of the display unit 110 so that the icon 131 canbe recognized as a display.

FIG. 4D shows an example of an image which is displayed on the displayunit 110 a predetermined period of time (e.g., 100 to 200 msec) afterthe state shown in FIG. 4C. As shown in FIG. 4D, the system controller102 instructs the display control unit 122 to minimize the transparencyof the icon 131 or maximize the luminance of the display unit 110 sothat the icon 131 can be perfectly recognized as a display. The displaycontrol unit 122 performs control according to the instruction from thesystem controller 102 to minimize the transparency of the icon 131 ormaximize the luminance of the display unit 110.

FIG. 5 is an illustrative diagram showing a graph indicating an exampleof changes in the transparency of the icon 131 displayed on the displayunit 110 (or the luminance of the display unit 110) of the head-mounteddisplay 100 according to an embodiment of the present disclosure. In thegraph shown in FIG. 5, the horizontal axis represents time, and thevertical axis represents the transparency of the icon 131 (or theluminance of the display unit 110). It is assumed that time t1 is a timepoint corresponding to the state shown in FIG. 4A, time t2 is a timepoint corresponding to the state shown in FIG. 4B, time t3 is a timepoint corresponding to the state shown in FIG. 4C, and time t4 is a timepoint corresponding to the state shown in FIG. 4D. In the head-mounteddisplay 100 according to an embodiment of the present disclosure, thetransparency of the icon 131 (or the luminance of the display unit 110)indicating the arrival of a mail, call, or the like is thus graduallychanged so that the user is prevented from being involuntarily attractedby the animation.

After the icon 131 is clearly displayed at time t4, the systemcontroller 102 may adjust the transparency of the icon 131 or theluminance of the display unit 110 so that the icon 131 is again notdisplayed, as indicated by a solid-state line in the graph shown in FIG.5. Alternatively, as indicated by a dashed line in the graph shown inFIG. 5, the transparency of the icon 131 or the luminance of the displayunit 110 may not be changed.

After displaying the icon 131 on the display unit 110 as shown in FIGS.4A to 4C, the system controller 102, when receiving a second incomingmail, call, or the like, may newly display an icon 131 corresponding tothe second incoming mail, call, or the like on the display unit 110 asshown in FIG. 4A to 4C, or alternatively, may erase the previouslydisplayed icon 131 from the display unit 110, and then display an icon131 corresponding to the second incoming mail, call, or the like on thedisplay unit 110 as shown in FIG. 4A to 4C.

Thus, the head-mounted display 100 according to an embodiment of thepresent disclosure gradually display the icon 131 on the display unit110 by changing the transparency of the icon 131 (or the luminance ofthe display unit 110) indicating the arrival of a mail, call, or thelike over time. When only one icon 131 is displayed on the display unit110, the system controller 102 may change either the transparency of theicon 131 or the luminance of the display unit 110. However, if two ormore icons 131 are displayed on the display unit 110, then when all theicons 131 are uniformly changed, the system controller 102 may changethe luminance of the display unit 110 over time, or then when only aparticular icon(s) 131 is changed, the system controller 102 may changethe transparency of the icon(s) 131 over time.

Note that the head-mounted display 100 according to an embodiment of thepresent disclosure may be capable of switching between a display processof displaying the icon 131 on the display unit 110 so that the icon 131gradually becomes clearly visible as shown in FIGS. 4A to 4C, and adisplay process of clearly displaying the icon 131 on the display unit110 from the beginning. Such switching may be set by the user or may beautomatically set according to a situation where the head-mounteddisplay 100 is used. For example, in a situation where a problem willarise if the user's field of vision is suddenly blocked, such as whenthe user is outside, the head-mounted display 100 may perform a displayprocess of displaying the icon 131 on the display unit 110 so that theicon 131 gradually becomes clearly visible as shown in FIGS. 4A to 4C,according to settings provided by the user themselves or settingsautomatically provided by the head-mounted display 100.

The head-mounted display 100 according to an embodiment of the presentdisclosure may change the transparency of an image indicating thearrival of a mail, call, or the like (or the luminance of the displayunit 110), according to the intensity of ambient light. Specifically,when ambient light is weak, then even if the amount of a change in thetransparency of an image (or the luminance of the display unit 110) issmall, the user can satisfactorily recognize the change. When ambientlight is strong, it is difficult for the user to recognize such achange. Therefore, the head-mounted display 100 according to anembodiment of the present disclosure may measure the intensity ofambient light using a sensor capable of measuring the intensity ofambient light, such as a luminance sensor, a camera, or the like, in thesensor unit 101, and adjust the amount of a change in transparency orluminance according to the intensity of ambient light.

FIG. 6A is an illustrative diagram showing a graph indicating an exampleof changes in the transparency of the icon 131 displayed on the displayunit 110 (or the luminance of the display unit 110) of the head-mounteddisplay 100 according to an embodiment of the present disclosure. InFIG. 6A, reference sign 141 indicates the transition of a display of thetransparency (or the luminance of the display unit 110) when theintensity of ambient light is weak, reference sign 142 indicates thetransition of a display of the transparency (or the luminance of thedisplay unit 110) when the intensity of ambient light is stronger thanin the case of reference sign 141, and reference sign 143 the transitionof a display of the transparency (or the luminance of the display unit110) when the intensity of ambient light is stronger than in the case ofreference sign 142. The head-mounted display 100 according to anembodiment of the present disclosure thus gradually changes thetransparency of the icon 131 (or the luminance of the display unit 110)indicating the arrival of a mail, call, or the like according to theintensity of ambient light, and thereby prevents the user from beinginvoluntarily attracted by the animation.

Note that, as in the example shown in FIG. 5, after the icon 131 isclearly displayed, the system controller 102 may adjust the transparencyof the icon 131 or the luminance of the display unit 110 so that theicon 131 is again not displayed, or alternatively, may not change thetransparency of the icon 131 or the luminance of the display unit 110.

Although, in the example shown in FIG. 6A, the time it takes to fullyrecognize the icon 131 as a display is the same irrespective of theintensity of ambient light, the present disclosure is not limited tosuch an example. The head-mounted display 100 according to an embodimentof the present disclosure may perform display control so that the timeit takes to fully recognize the icon 131 as a display is increased withan increase in the intensity of ambient light.

FIG. 6B is an illustrative diagram showing a graph indicating an exampleof changes in the transparency of the icon 131 displayed on the displayunit 110 (or the luminance of the display unit 110) of the head-mounteddisplay 100 according to an embodiment of the present disclosure. FIG.6B shows an example of changes in the transparency of the icon 131 (orthe luminance of the display unit 110) in a case where the time it takesto fully recognize the icon 131 as a display is increased with anincrease in the intensity of ambient light.

The above technique of changing the transparency of an icon or displayinformation (or the luminance of the display unit 110) can be combinedwith a sensor value which is obtained by detecting a motion of theuser's line of sight, head, or the like using the sensor unit 101. Forexample, if an operable icon or a message continues to be displayed infront of the eyes, a portion of the field of view is blocked, andtherefore, the user is likely to feel uncomfortable. With this in mind,a display control example will be described in which display control isperformed in combination with the user's line of sight so that the useris prevented from feeling uncomfortable.

FIGS. 7A to 7C are illustrative diagrams showing examples of an imagedisplayed on the display unit 110 of the head-mounted display 100according to an embodiment of the present disclosure, where an icon isdisplayed in an illustrative manner when an interrupt, such as thearrival of a mail or the like, occurs.

In FIGS. 7A to 7C, a point 150 indicates the position of the line ofsight of the user wearing the head-mounted display 100. As shown in FIG.7A, when the line of sight is located away from a region where the icon131 is displayed, the system controller 102 instructs the displaycontrol unit 122 to cause the display unit 110 to increase thetransparency of the icon 131 or decrease the luminance of the displayunit 110.

As shown in FIGS. 7B and 7C, when the user's line of sight is close tothe region where the icon 131 is displayed, the system controller 102instructs the display control unit 122 to cause the display unit 110 tochange the transparency of the icon 131 (or the luminance of the displayunit 110) so that the icon 131 is clearly displayed instead of beingtransparent.

The head-mounted display 100 according to an embodiment of the presentdisclosure controls the display of an icon according to the place wherethe user's line of sight is located, so that the icon 131, which isusually not displayed in front of the eyes, is displayed on the displayunit 110 only when the user wearing the head-mounted display 100performs an operation of changing the line of sight with a thought ofviewing information.

FIG. 8 is an illustrative diagram showing a specific example of acalculation method which is used during execution of display control onthe icon 131 according to the user's line of sight. A coordinate pointof the icon 131 in a display region is represented by (X1, Y1), and acoordinate point of the line of sight in the display region isrepresented by (X2, Y2). A distance A between the two points can becalculated by A={(X2−X1)²+(Y2−Y1)²}^(0.5). The system controller 102 mayinstruct the display control unit 122 to increase the transparency (ordecreases the luminance) so that the icon 131 becomes transparent when Ais great, and decrease the transparency (or increase the luminance) sothat the icon 131 becomes clearly visible when A is small.

The head-mounted display 100 according to an embodiment of the presentdisclosure may detect an angle of the user's head using the sensor unit101 instead of the user's line of sight, and similarly perform displaycontrol on the icon using the angle.

FIGS. 9A to 9C are illustrative diagrams showing examples of an imagedisplayed on the display unit 110 of the head-mounted display 100according to an embodiment of the present disclosure, where an icon isdisplayed in an illustrative manner when an interrupt, such as thearrival of a mail or the like, occurs.

As shown in FIG. 9A, the system controller 102, when detecting, on thebasis of data acquired by the sensor unit 101, that the user faces frontwithout inclining their neck, instructs the display control unit 122 tocause the display unit 110 to increase the transparency of the icon 131or decrease the luminance of the display unit 110.

As shown in FIGS. 9B and 9C, when the inclination of the user's neckgradually increases, so that the sensor unit 101 detects that the userfaces their feet, on the basis of acquired data, the system controller102 instructs the display control unit 122 to cause the display unit 110to change the transparency of the icon 131 (or the luminance of thedisplay unit 110) so that the icon 131 is clearly displayed instead ofbeing transparent.

Although the head-mounted display 100 according to an embodiment of thepresent disclosure thus performs display control to clearly display theicon 131 according to the angle of the user's head, the presentdisclosure is not limited to this example. For example, the systemcontroller 102 may perform display control to clearly display the icon131 if the amount of a motion of the user's head exceeds a predeterminedthreshold.

The head-mounted display 100 according to an embodiment of the presentdisclosure may detect the rate of movement of the user using the sensorunit 101, and similarly perform display control on an icon using themovement rate. Specifically, when the user is walking, then if an iconis displayed on the display unit 110 to attract the user's attention,the user's attention is distracted from the scene in front of the user,which is dangerous. Therefore, the head-mounted display 100 according toan embodiment of the present disclosure may perform display control todisplay a thin icon when the user is walking, and a clearly visible iconwhen the user is standing.

When the head-mounted display 100 according to an embodiment of thepresent disclosure detects the rate of movement of the user, andperforms display control on an icon using the movement rate, thehead-mounted display 100 may perform display control to clearly displaythe icon if the icon is intended for emergency notification, even whenthe user is walking. Examples of emergency notification may include thereception of a call or the arrival of a mail from a particular person, areminder having high priority, and the like. The user of thehead-mounted display 100 may decide what is emergency notification, andemergency notification is not limited to particular things.

The head-mounted display 100 according to an embodiment of the presentdisclosure may detect the state of the user's activity using the imagecapture unit 113 or the audio input unit 116 in addition to the sensorunit 101, and perform display control on an icon to be displayed on thedisplay unit 110, using the result of the detection of the user'sactivity state.

For example, when the user is driving a car while wearing thehead-mounted display 100, then if it is found that the steering wheel ofthe car is included in an image captured by the image capture unit 113,or the sound of the engine is included in sounds collected by the audioinput unit 116, the system controller 102 determines that the user isdriving a car. When the user is driving a car, then if an icon isdisplayed on the display unit 110 to attract the user's attention, theuser's attention is distracted from the scene in front of the user,which is very dangerous, as in the above case where the user is walking.Therefore, when it is found that the user is driving a car, the systemcontroller 102 may perform display control to display a thin icon or noicon when the user is driving a car, and a clearly visible icon asdescribed above when the car is standing.

In the head-mounted display 100 according to an embodiment of thepresent disclosure, if it is found that the sound of human conversationis included in sounds collected by the audio input unit 116, the systemcontroller 102 determines that the user using the head-mounted display100 is talking with another person. When the user using the head-mounteddisplay 100 is talking with another person, then if an icon is displayedon the display unit 110 to attract the user's attention, the user'sattention is distracted from the conversation with that person, whichhinders smooth communication. Therefore, if it is found that the user istalking with another person, the system controller 102 may performdisplay control to display a thin icon or no icon when the user istalking, and a clearly visible icon as described above when theconversation is interrupted.

Thus, the head-mounted display 100 according to an embodiment of thepresent disclosure can recognize a situation where the user is using thehead-mounted display 100, on the basis of an image captured by the imagecapture unit 113 or sounds collected by the audio input unit 116, andcontrol the display of an icon on the display unit 110 according to theuser's situation.

In the foregoing, examples have been described in which an icon isgradually displayed on the display unit 110 by changing the transparencyof the icon or the luminance of the display unit 110. For example, thehead-mounted display 100 according to an embodiment of the presentdisclosure may gradually clearly display an icon on the display unit 110by gradually increasing the size of the icon.

In the foregoing, functional configuration examples of the head-mounteddisplay 100 according to an embodiment of the present disclosure havebeen described. Next, operation examples of the head-mounted display 100according to an embodiment of the present disclosure will be described.

[1.3. Operation Examples of Head-Mounted Display]

FIG. 10 is a flowchart showing an operation example of the head-mounteddisplay 100 according to an embodiment of the present disclosure. FIG.10 shows an operation example of the head-mounted display 100 which isperformed when the head-mounted display 100 performs a process ofdisplaying, on the display unit 110, an image (e.g., a predeterminedicon) indicating the presence of information of which the user is to benotified, such as the arrival of a call or mail, or the like. Theoperation example of the head-mounted display 100 according to anembodiment of the present disclosure will now be described withreference to FIG. 10.

The head-mounted display 100 according to an embodiment of the presentdisclosure initially waits until the occurrence of a process ofdisplaying, on the display unit 110, an icon indicating the presence ofinformation of which the user is to be notified, such as the arrival ofa call or mail, or the like (step S101). The head-mounted display 100,when detecting the occurrence of the process of displaying an icon onthe display unit 110 (step S101: Yes), displays an icon on the displayunit 110 while adjusting the transparency of the icon (or the luminanceof the display unit 110) (step S102). The adjustment and display processin step S102 is, for example, performed by the display control unit 122according to an instruction from the system controller 102.

The transparency of an icon (or the luminance of the display unit 110)may be adjusted so that, as described above, the icon may be moreclearly displayed over time, the icon may be more clearly displayedaccording to the position of the line of sight, the icon may be moreclearly displayed according to the inclination of the head, or the iconmay be more clearly displayed according to the rate of movement of theuser.

By thus displaying an image indicating the arrival of a mail, call, orthe like on the display unit 110 while changing the transparency of anicon (or the luminance of the display unit 110), the field of vision ofthe user wearing the head-mounted display 100 can be ensured while theuser is kept safe.

The head-mounted display 100 according to an embodiment of the presentdisclosure may perform display control to gradually clearly display anicon using information about color in the user's field of vision. Forexample, when the user using the head-mounted display 100 is in a roomhaving white walls, the system controller 102 initially performs displaycontrol to display a white icon on the display unit 110. By initiallydisplaying a white icon on the display unit 110 when the user using thehead-mounted display 100 is in a room having white walls, thehead-mounted display 100 according to an embodiment of the presentdisclosure can cause the user not to notice that the icon is displayedon the display unit 110.

After displaying the white icon on the display unit 110, the systemcontroller 102 performs display control to gradually change the color ofthe icon to the original color, or a different color if the originalcolor is white. By such display control, the head-mounted display 100according to an embodiment of the present disclosure can avoiddisplaying information which is involuntarily noticed by the user orblocks the field of view.

Alternatively, for example, the system controller 102 initially performsdisplay control to display, on the display unit 110, an icon havingcolors from which a green component is removed. Green is a color whichis most strongly sensed by humans. Therefore, by displaying an iconhaving colors from which a green component is removed, the head-mounteddisplay 100 according to an embodiment of the present disclosure canavoid displaying information which is involuntarily noticed by the useror blocks the field of view.

2. CONCLUSION

As described above, according to an embodiment of the presentdisclosure, provided is the see-through head-mounted display 100 which,when displaying information which blocks a portion of the user's fieldof view displays the information gradually clearly while adjusting thetransparency of an icon or the luminance of the display unit 110. Thehead-mounted display 100 according to an embodiment of the presentdisclosure, when displaying information of which the user is to benotified on the display unit 110, displays the information graduallyclearly while adjusting the transparency of an icon or the luminance ofthe display unit 110, for example, over time, according to the positionof the line of sight, according to the inclination of the head, oraccording to the rate of movement of the user.

By thus displaying information gradually clearly while adjusting thetransparency thereof or the luminance of the display unit 110, thehead-mounted display 100 according to an embodiment of the presentdisclosure can avoid displaying information which is involuntarilynoticed by the user or blocks the field of view and thereby reduce adanger to the user when the user is using the head-mounted display 100.

In the above embodiments, examples have been described in which thedisplay control on the display unit 110 is performed by the displaycontrol unit 122 according to an instruction from the system controller102 included in the head-mounted display 100. The present disclosure isnot limited to these examples. For example, the display control on thedisplay unit 110 may be performed by a device separated from thehead-mounted display 100, which is connected to the head-mounted display100 by wire or wirelessly.

Steps in processes executed by devices in this specification are notnecessarily executed chronologically in the order described in asequence chart or a flow chart. For example, step S in processesexecuted by devices may be executed in a different order from the orderdescribed in a flow chart or may be executed in parallel.

Further, a computer program can be created which causes hardware such asa CPU, ROM, or RAM, incorporated in each of the devices, to function ina manner similar to that of structures in the above-described devices.Furthermore, it is possible to provide a recording medium having thecomputer program recorded thereon. Moreover, by configuring respectivefunctional blocks shown in a functional block diagram as hardware, thehardware can achieve a series of processes.

Note that software which is used to implement the user interface orapplication described in the above embodiments may be implemented as aweb application which is used through a network, such as the Internet orthe like. The web application may be implemented using, for example, amarkup language, such as HyperText Markup Language (HTML), StandardGeneralized Markup Language (SGML), Extensible Markup Language (XML), orthe like.

The preferred embodiment(s) of the present disclosure has/have beendescribed above with reference to the accompanying drawings, whilst thepresent disclosure is not limited to the above examples. A personskilled in the art may find various alterations and modifications withinthe scope of the appended claims, and it should be understood that theywill naturally come under the technical scope of the present disclosure.

In addition, the effects described in the present specification aremerely illustrative and demonstrative, and not limitative. In otherwords, the technology according to the present disclosure can exhibitother effects that are evident to those skilled in the art along with orinstead of the effects based on the present specification.

Additionally, the technology of the present disclosure may also beconfigured as below.

(1)

A display control device including:

a situation acquisition unit configured to acquire information about asituation where a see-through display worn on a user in front of theuser's eye is being used; and

a display control unit configured to perform display control on thesee-through display using the information acquired by the situationacquisition unit so that a display of the information on the see-throughdisplay gradually becomes clearly visible.

(2)

The display control device according to (1),

wherein the situation acquisition unit acquires a state of ambientlight, and

wherein the display control unit performs display control so that thedisplay of the information on the see-through display gradually becomesclearly visible according to the state of the ambient light.

(3)

The display control device according to (2),

wherein the display control unit performs display control so that thetime it takes for the display of the information on the see-throughdisplay to become clearly visible increases with an increase in anintensity of the ambient light.

(4)

The display control device according to (1),

wherein the situation acquisition unit acquires a state of a line ofsight of the user viewing the see-through display, and

wherein the display control unit performs display control so that thedisplay of the information on the see-through display gradually becomesclearly visible according to the state of the line of sight.

(5)

The display control device according to (1),

wherein the situation acquisition unit acquires a state of a motion of ahead of the user viewing the see-through display, and

wherein the display control unit performs display control so that thedisplay of the information on the see-through display gradually becomesclearly visible according to the state of the motion of the head.

(6)

The display control device according to (1),

wherein the situation acquisition unit acquires a state of aninclination of a head of the user viewing the see-through display, and

wherein the display control unit performs display control so that thedisplay of the information on the see-through display gradually becomesclearly visible according to a degree of the inclination of the head.

(7)

The display control device according to (1),

wherein the situation acquisition unit acquires a state of an activityof the user viewing the see-through display, and

wherein the display control unit performs display control so that thedisplay of the information on the see-through display gradually becomesclearly visible according to the state of the activity.

(8)

The display control device according to (1),

wherein the situation acquisition unit acquires a background at which aline of sight of the user viewing the see-through display is aimed, and

wherein the display control unit performs display control so that thedisplay of the information on the see-through display gradually becomesclearly visible according to a state of the background.

(9)

The display control device according to (8),

wherein the display control unit performs display control so that thedisplay of the information on the see-through display gradually becomesclearly visible according to a color of the background.

(10)

The display control device according to (1),

wherein the display control unit performs display control to change atransparency of the display of the information on the see-throughdisplay so that the display of the information on the see-throughdisplay gradually becomes clearly visible.

(11)

The display control device according to (1),

wherein the display control unit performs display control to change aluminance of the see-through display so that the display of theinformation on the see-through display gradually becomes clearlyvisible.

(12)

A display control method including:

acquiring information about a situation where a see-through display isbeing used, and

performing display control on the see-through display using the acquiredinformation so that a display of the information on the see-throughdisplay gradually becomes clearly visible.

(13)

A computer program for causing a computer to execute:

acquiring information about a situation where a see-through display isbeing used; and

performing display control on the see-through display using the acquiredinformation so that a display of the information on the see-throughdisplay gradually becomes clearly visible.

REFERENCE SIGNS LIST

-   100 head-mounted display-   101 sensor unit-   102 system controller-   110 display unit-   111 sensor signal processing unit-   112 sensor control unit-   113 image capture unit-   114 captured image signal processing unit-   115 image capture control unit-   116 audio input unit-   117 audio output unit-   118 audio signal processing unit-   119 audio generation unit-   120 image generation unit-   121 displayed image processing unit-   122 display control unit-   123 display drive unit-   124 communication unit-   125 storage unit-   131 icon

1-13. (canceled)
 14. A display control device comprising: at least oneprocessor configured to: acquire notification information to notify auser of a see-through head mounted display of an arrival of at least oneof a mail or a call; and control, based on the notification information,the see-through head mounted display to: initiate display of an iconimage indicating the notification information, and after initiating thedisplay of the icon image, gradually increase visibility of the iconimage.
 15. The display control device according to claim 14, wherein theat least one processor is further configured to: determine whether theuser is outside; control, based on the notification information anddetermination that the user is not outside, the see-through head mounteddisplay to initiate the display of the icon image at a first visibility;and control, based on the notification information and determinationthat the user is outside, the see-through head mounted display toinitiate the display of the icon image at a second visibility lower thanthe first visibility.
 16. The display control device according to claim14, wherein the at least one processor is further configured to: acquireambient information of an intensity of ambient light; and control, basedon the ambient information, the see-through head mounted display to:increase the visibility of the icon image as the intensity of theambient light increases, and increase a time it takes to finishincreasing the visibility of the icon image as the intensity of theambient light increases.
 17. The display control device according toclaim 14, wherein the at least one processor is further configured to:determine whether a state of the user is a movement state or anon-movement state based on a rate of movement of the user; control,based on the notification information and determination that the stateof the user is the non-movement state, the see-through head mounteddisplay to display the icon image at a third visibility; and control,based on the notification information and determination that the stateof the user is the movement state, the see-through head mounted displayto display the display of the icon image at a fourth visibility lowerthan the third visibility.
 18. The display control device according toclaim 17, wherein the movement state is a walking state, and wherein thenon-movement state is a standing state.
 19. The display control deviceaccording to claim 14, wherein the at least one processor is furtherconfigured to: control, based on the notification information, thesee-through head mounted display to: after initiating the display of theicon image, gradually decrease a transparency of the icon image.
 20. Thedisplay control device according to claim 14, wherein the at least oneprocessor is further configured to: control, based on the notificationinformation, the see-through head mounted display to: after initiatingthe display of the icon image, gradually increase a luminance of thesee-through head mounted display.
 21. The display control deviceaccording to claim 14, wherein the at least one processor is furtherconfigured to: control, based on the notification information, thesee-through head mounted display to: after the increase of thevisibility of the icon image is finished, gradually decrease thevisibility of the icon image.
 22. The display control device accordingto claim 14, wherein the at least one processor is further configuredto: control the see-through head mounted display to: gradually increasethe visibility of the icon image according to a state of a line of sightof the user viewing the see-through head mounted display.
 23. Thedisplay control device according to claim 22, wherein the at least oneprocessor is further configured to: control, when the line of sight ofthe user is within a predetermined distance to a region where the iconimage is displayed, the see-through head mounted display to: change atransparency of the icon image so that the increase of the visibility ofthe icon image is finished.
 24. The display control device according toclaim 14, wherein the at least one processor is further configured to:control the see-through head mounted display to: gradually increase thevisibility of the icon image according to a degree of an inclination ofa head of the user viewing the see-through head mounted display.
 25. Thedisplay control device according to claim 14, wherein the at least oneprocessor is further configured to: change the visibility of the iconimage by decreasing a green component of the icon image than other colorcomponents of the icon image.
 26. The display control device accordingto claim 14, wherein the at least one processor is further configuredto: determine a state of an activity of the user viewing the see-throughdisplay; and control the see-through head mounted display to: graduallyincrease the visibility of the icon image according to the state of theactivity.
 27. The display control device according to claim 14, whereinthe at least one processor is further configured to: determine abackground at which a line of sight of the user viewing the see-throughdisplay is aimed; and control the see-through head mounted display to:gradually increase the visibility of the icon image according to a stateof the background.
 28. A display control method comprising: acquiringnotification information to notify a user of a see-through head mounteddisplay of an arrival of at least one of a mail or a call; andcontrolling, based on the notification information, the see-through headmounted display to: display an icon image indicating the notificationinformation; and after displaying of the icon image, gradually increasevisibility of the icon image.
 29. A non-transitory computer-readablestorage medium having embodied thereon a program, which when executed bya computer causes the computer to execute a method, the methodcomprising: acquiring notification information to notify a user of asee-through head mounted display of an arrival of at least one of a mailor a call; and controlling, based on the notification information, thesee-through head mounted display to: display an icon image indicatingthe notification information; and after displaying of the icon image,gradually increase visibility of the icon image.